/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.connector.jdbc;

import org.apache.flink.annotation.Experimental;
import org.apache.flink.api.common.functions.RuntimeContext;
import org.apache.flink.connector.jdbc.internal.JdbcBatchingOutputFormat;
import org.apache.flink.connector.jdbc.internal.connection.JdbcConnectionProvider;
import org.apache.flink.connector.jdbc.internal.connection.SimpleJdbcConnectionProvider;
import org.apache.flink.connector.jdbc.internal.executor.JdbcBatchStatementExecutor;
import org.apache.flink.types.Row;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.function.Function;

import static org.apache.flink.connector.jdbc.utils.JdbcUtils.setRecordToStatement;

/**
 * OutputFormat to write Rows into a JDBC database.
 * The OutputFormat has to be configured using the supplied OutputFormatBuilder.
 */
@Experimental
public class JdbcOutputFormat extends JdbcBatchingOutputFormat<Row, Row, JdbcBatchStatementExecutor<Row>> {

	private static final long serialVersionUID = 1L;

	private static final Logger LOG = LoggerFactory.getLogger(JdbcOutputFormat.class);

	private JdbcOutputFormat(JdbcConnectionProvider connectionProvider, String sql, int[] typesArray, int batchSize) {
		super(
			connectionProvider,
			new JdbcExecutionOptions.Builder().withBatchSize(batchSize).build(),
			ctx -> createRowExecutor(sql, typesArray, ctx),
			JdbcBatchingOutputFormat.RecordExtractor.identity());
	}

	private static JdbcBatchStatementExecutor<Row> createRowExecutor(String sql, int[] typesArray, RuntimeContext ctx) {
		JdbcStatementBuilder<Row> statementBuilder = (st, record) -> setRecordToStatement(st, typesArray, record);
		return JdbcBatchStatementExecutor.simple(
			sql,
			statementBuilder,
			ctx.getExecutionConfig().isObjectReuseEnabled() ? Row::copy : Function.identity());
	}

	public static JdbcOutputFormatBuilder buildJdbcOutputFormat() {
		return new JdbcOutputFormatBuilder();
	}

	/**
	 * Builder for {@link JdbcOutputFormat}.
	 */
	public static class JdbcOutputFormatBuilder {
		private String username;
		private String password;
		private String drivername;
		private String dbURL;
		private String query;
		private int batchSize = JdbcExecutionOptions.DEFAULT_SIZE;
		private int[] typesArray;

		private JdbcOutputFormatBuilder() {}

		public JdbcOutputFormatBuilder setUsername(String username) {
			this.username = username;
			return this;
		}

		public JdbcOutputFormatBuilder setPassword(String password) {
			this.password = password;
			return this;
		}

		public JdbcOutputFormatBuilder setDrivername(String drivername) {
			this.drivername = drivername;
			return this;
		}

		public JdbcOutputFormatBuilder setDBUrl(String dbURL) {
			this.dbURL = dbURL;
			return this;
		}

		public JdbcOutputFormatBuilder setQuery(String query) {
			this.query = query;
			return this;
		}

		public JdbcOutputFormatBuilder setBatchSize(int batchSize) {
			this.batchSize = batchSize;
			return this;
		}

		public JdbcOutputFormatBuilder setSqlTypes(int[] typesArray) {
			this.typesArray = typesArray;
			return this;
		}

		/**
		 * Finalizes the configuration and checks validity.
		 *
		 * @return Configured JdbcOutputFormat
		 */
		public JdbcOutputFormat finish() {
			return new JdbcOutputFormat(new SimpleJdbcConnectionProvider(buildConnectionOptions()), query,
				typesArray, batchSize);
		}

		public JdbcConnectionOptions buildConnectionOptions() {
			if (this.username == null) {
				LOG.info("Username was not supplied.");
			}
			if (this.password == null) {
				LOG.info("Password was not supplied.");
			}

			return new JdbcConnectionOptions.JdbcConnectionOptionsBuilder()
				.withUrl(dbURL)
				.withDriverName(drivername)
				.withUsername(username)
				.withPassword(password)
				.build();
		}
	}

}
